Nonset automatic phonograph stop



Sept. 11, 1923.

L. S. HOPKINS NCNSET AUTOMATIC PHONOGRAPH STOP Filed July 21 1922 Patented Sept. ll, 1923.

meme

LUTHER S. HOPKINS, OF DUBUQUE, IOWA.

. NONSIE ZT AUTOMATIC PHQNOGRAPH STOP.

Continuation of application Serial No.

To all whom 2'2- may concern: 7 7

Be it known that I, LUTHER S. HOPKINS, a citizen of the United States, and a resident of the city ofDubuque, in the county of Dubuque and State of Iowa, have invented certain new and useful Improvements in a N onset Automatic Phonograph Stop; and I do hereby declare that the folv lowing is a full, clear, and exact description of the same, reference being had to the accompanying drawings and to the numerals of'reference marked thereon, which form a part of this specification.

This invention .relates to an improved type of automatic non-set phonograph stop wherein a member attached to and movable with the tone arm is adapted, by frictional contact with a mechanism mounted on a slidable bar carrying a brake shoe, to cause engagement of the brake shoe with theturntable when the tone arm ceases to move radially across a record. I

This application is a continuation of my pending application for a non-set phonograph stop, filedOct. 28,1921, Serial No. 511,032.

It is an object of this invention to pro .vide a phonograph stop adapted to automatically stop the phonograph motor when the playing needle reaches the innermost groove of a phonographrecord.

It is also an object of this invention to provide a phonograph stop that is automatically reset by the act of restarting the phonograph.

It is a further object of this invention to provide a phonographf stop' mechanism adapted to be actuated by a projection on the phonograph spindle when the tone arm ceases to move toward the center of the record for any reason.

It is an important object of this invention to provide amechanism adapted to provide either a stop fora phonograph turntable, or the combination of a stop and a switch for an electrically driven phonograph adapted to release upon stoppage of the movement'of the tone arm. 7 It is a further important object of this invention to provide a non-set automatic phonograph stop wherein a member-actuated by a-turntable. spindle and means car- I -ried by a tone arm are adapted to coact with control means. on .a slidable brake shoe bar'to cause automatic stopping ofv the phonograph at a predetermined time.

511,022, filed October as, 1921. Serial No. 576,441.

This application filed July 21,

Other and further important objects of this invention will be apparent from the disclosures in the specification and the ac-' companying drawings.

The invention (in a preferred form) is illustrated in the drawings and hereinafter more fully described.

On the drawings: 7

Figure l is a top plan view of a phonograph showing the record and turntable partly broken away to disclose a stop mechanism embodying the preferred form of this invention as applied to a spring motor phonograph.

Figure 2 is an enlarged section on the line 2-2 of Figure 1. I

Figure 3 is an enlarged fragmentary view of the release mechanism just prior to operation thereof. 1

Figure 4 is a view similar to Fig. 3 disclosing a locking movement about to cause release of the brake shoe bar.

As shown on the drawings: The reference numeral 1 indicates, a phonograph cabinet provided with a usual motor board 2, turntable shaft or spindle 3-, and turntable 4 provided with a depending flange 5 around the periphery thereof.

A grooved disc phonograph record 6 is positioned on the turntable by means of the spindle 3. A swinging tone arm 7 is supported in a standard or base 8 and carend a circular segment 12, is rigidly attached to the supported end of the tone arm and projects beneath the turntable 4. The axis of the circular segment 12 corresponds to that of the tone arm 7 and as the tone arm swings over the turntable the segment swings correspondingly beneath the turntable. The ends 13 of the circular seg ment 12 are bentbackwardly to permit engagement of the segment with a spring-actuated member to be described hereinafter.

Radially positioned upon the motor board 2 below the turntable, 4 is a slidable starting or brake bar 1 1-, the outer end of which projects beyond the flange 5 of the turn table and is bent upwardly to form aninof suitable frictional material, in a position to bear against the flanges of the turntable when the brake bar 14' is released. The bar 14: is providedwith a straight longitudinal guide slot 18'near the" brake shoe holder 16 and with an L-shaped slot 19 located near the other end of the bar. Screws 20project through the slots 18 and "19 and through washers 21 disposed above andbelow the bar 1 1. Struck up from the bar it between the slots 18 and- 19 is a lug 22 to which one end of 'a coil spring 23 issecured, The other end of the spring 23'is secured to the motor board 2.

The inner end of the bar 1 1 is bent upwardly at 24 to afford a raised support 25 for an inserted pivot screw 26. Ad acent the bend 2 1 a stop lug 27 is struck upward 1y from the bar 14. Rotatably mounted on contact the various points of the star wheel 31 to cause rotation thereof when the brake bar 14: is in itsinner position. The arm'29 of the bell crank 28 is forked with the ends 30 engages with the fork 33 33 and 3 1 of the fork re-entrant so that as the star wheel revolves counterclockwise the pins 30 will act on the inner surface of the form end 33 to throw the bell crank 28 to the left, bringing the end 34 into a position to interfere withoneof the pins 301 after av further half revolution. The short arm 35 of the bell crank 28 supports a spring 36 tion member 37 by means of; a channel shaped holder 38 'having'a comparatively stiff extension :39, the end of which rests on the lug 27. The extension 39, in connection withthe spring- 36, serves to keep the lever arm 29' normally at its extreme right-position and tosnap it back again after a pin to throw the lever to the -left, I The operation is as follows: r This non-set automatic phonograph stop is adaptable for usewith practically all types-of phonographs in place of the ordinary brake'for' the turntable thereof.

It will be apparent that when the tone arm is swung out to engage the stylus in the outermostgroove of the record, the segment carrying arm 11 swings with it, and engages with the friction member 3'7 only when most of therecord has been played, i. 'e., when thetone arm has swung inwardly fora considerable distance. Normally the brake bar 14 is in its outermost position wherein the brake shoe 17 is in contact with the turn- -table flange -5 holding the turntable and driving 'm'otor stationary. To 1 startv the phonograph the brake bar" 14 is pushed inwardly by the thumbpiece 15, which is conveniently located in place of the usual manually operatingbrake, until the curved end of the L slot 19 is reached, when the spring 23 acts to pull at-he. brake bar sideways to permit the screw-to. seat in the curved end of slot 19 to hold the brake bar in its inner position with" the brake shoe 17 out of engagement with the turntable flange 5.

'Rotation of the/turntable spindle 3 causes the projection 32 thereon to engage with one of the points of the star wheel 31 to cause a partial revolution thereof at each revolution of the spindle, when the brakebar- 14 is in its inner position.- When, by the rotation ofthe star wheel, one of the pins 30 engages'wi-th the inner surface fork'end 33- of the lever 28, said lever is temporarily swung to theleft until-the pin slips past the end- 33 J of the fork,' when the'spring 36 serves to j snap the lever 28 back into its normal position. It will be apparentthat the star wheel 31 and lever 28 function in 'amanner' somewhat similar to the escapementwheel and v mal position after engaging with. one. of

the pins 30 by overcoming the tendency of the spring 36 to pull the'friction member 37 over the surface of the. segment. How ever, as long as the tone arm and segment 12 are moving inwardly, the segme'ht'carries the friction member along with itand so causes a return of the lever 28 into its normal position. 7 i a lVhen the stylus reaches: the last or inner groove of the record thetone arm and. segment stop moving inwardly thereby h'olding the friction member stationary until one of the pins 30 snaps the"1ever29i to the left when the, friction member holds the lever vin this position, where the fork end 7 34 is in a position to catch the in 'on its outer surface', as-showniin Fig. 4, aftera further half revolution of the star wheel, thus locking the star wheel, 'and 'cau sing the spindle projection 32 to throw the slidable brake bar slightly away from the spindle whereby the. curved end'of the L-sl'otais moved away from the screw '20-allowing'the spring 23, which was tensioned when the brake bar 17 was pushed inwardly,: to automatically act to slide the. brake bar outwardly into normal braking-position with the brake shoe 17 contacting the flange' pf the turntable, as with an. ordinary brake.

' It'will'be evident that thebrake'is not released by: swinging theitonearm 'outwardly, thus permitting a change off-records I or" shutting do wn the phonograph without attention from the operator.-*'- The vstop mechanism is automatic as it is reset by the act of starting the phonograph and So far as the operator is concerned needs absolutely no attention as all that is evident is the results produced thereby. In an apparatus such as a phonograph, such a simple automatic non-set stop is an immense advantage because very few of the users thereof have any knowledge of the mechanism of the phonograph.

I am aware that numerous details of construction may be varied through a wide range without departing from the principles of this invent-ion, and I therefore do not purpose limiting the patent granted otherwise than necessitated by the prior art.

I claim as my invention:

1. A non-set phonograph stop comprising a slidable bar, a control spring connected thereto, a brake sh-oe on said bar, a rotatable member on said bar, a member mounted on a phonographspindle for rotating said rotatable member, a bell crank pivoted on. said bar adapted to be actuated by said rotatable member, a spring carried by said bell crank, a friction member supported on said spring, an extension on said spring,

engaging said bar, and means carried by a phonograph tone arm adapted to frictionally engage said friction member and cause release to permit said control spring to slide the bar into a position wherein the brake shoe will stop the phonograph when the tone arm stops moving inwardly across a record.

2. A non-set phonograph stop comprising a spring controlled slidable stopping bar, a rotatable member on said bar, means mounted on the phonograph spindle adapted to rotate said rotatable member, a bell crank adapted to be actuated by said rotatable member, a spring carried by said bell crank, a holder thereon, a friction member in said holder, an extension on said holder frictionally contacting said bar, and means frictionally co-acting with said friction member adapted at a predetermined time to hold said bell crank in a position to interfere with the rotation of said rotatable member thereby causing release of said slidable bar and stopping of the phonograph.

In testimony whereof I have hereunto subscribed my name in the presence of two subscribing witnesses.

LUTHER S. HOPKINS. Witnesses:

Rom. W; CLEWELL, DRUSILLA E. FLAGG. 

